A range of buildings within an office campus have all been strengthened to protect against the risk of explosion in a nearby test centre. Royal HaskoningDHV was asked to assess the risk of explosions and ensure nearby buildings were sufficiently blast proof.

Blasts subject buildings to very high and very short loadings. The assessment of risk and identification of protective measures is a specialist area of expertise. In this case, it was complicated by the fact that none of the buildings were originally designed to be blast proof and that they varied in age and construction type. Equally, offices remained in use throughout the work, so disruption needed to be minimal.

Individual measures required for different structures

The potential risks were identified as extremely low but work was necessary to ensure complete confidence and safety for everyone who works on the campus. The buildings range from robust structures with pre-cast concrete walls and roof to a lightweight prefabricated site office with thin, fragile wall and roof structures. Individual measures were required for each building and special attention was given to commonly vulnerable facade openings like windows and doors.

Practical solutions necessary to avoid disruption to office activities

Solutions included applying blast-proof film to windows to keep panes intact and steel bars to catch a glass pane if it became detached from its mullions. The thin-walled building was provided with new, robust steel cladding.

“Projects like this require tailored, practical solutions which can be applied with minimal disruption to activities in the buildings. It’s quite different to newly designed buildings where blast requirements can be incorporated into the design,” explained Harm Kraaijenbrink, consulting engineer at Royal HaskoningDHV. “It’s not unusual for differences to be identified between existing buildings and original drawings so we also provided support during implementation to adapt and finetune our solutions where necessary.”